diff --git a/tools/precommit/Dockerfile b/tools/precommit/Dockerfile
index e833c45ead..c78ad7171b 100644
--- a/tools/precommit/Dockerfile
+++ b/tools/precommit/Dockerfile
@@ -19,21 +19,23 @@ RUN export DEBIAN_FRONTEND=noninteractive DEBCONF_NONINTERACTIVE_SEEN=true && \
     shellcheck \
   && rm -rf /var/lib/apt/lists/*
 
-# Install MarkdownLint.
+# Install markdownlint-cli and dependencies.
 # https://github.com/DavidAnson/markdownlint
-# https://github.com/igorshubovych/markdownlint-cli
-RUN npm install -g markdownlint-cli
+# https://github.com/igorshubovych/markdownlint-cli 
+WORKDIR /opt/cp2k-precommit
+COPY package.json package-lock.json ./
+RUN npm install .
+RUN ln -s /opt/cp2k-precommit/node_modules/markdownlint-cli/markdownlint.js /usr/bin/markdownlint
 
-# Install Black Python Formatter.
+# Install black, flask, gunicorn, and dependencies.
 # https://github.com/psf/black
-RUN pip3 install black
+COPY requirements.txt .
+RUN pip3 install -r requirements.txt
 
 # Clone cp2k repository (needed for CI mode).
 RUN git clone --quiet --recursive --single-branch -b master https://github.com/cp2k/cp2k.git /workspace/cp2k
 
 # Install Flask app.
-RUN pip3 install flask gunicorn
-WORKDIR /opt/cp2k-precommit
 COPY precommit_server.py .
 
 ARG REVISION
diff --git a/tools/precommit/package-lock.json b/tools/precommit/package-lock.json
new file mode 100644
index 0000000000..99319bb00c
--- /dev/null
+++ b/tools/precommit/package-lock.json
@@ -0,0 +1,257 @@
+{
+  "name": "cp2k-precommit",
+  "version": "1.0.0",
+  "lockfileVersion": 1,
+  "requires": true,
+  "dependencies": {
+    "argparse": {
+      "version": "1.0.10",
+      "resolved": "https://registry.npmjs.org/argparse/-/argparse-1.0.10.tgz",
+      "integrity": "sha512-o5Roy6tNG4SL/FOkCAN6RzjiakZS25RLYFrcMttJqbdd8BWrnA+fGz57iN5Pb06pvBGvl5gQ0B48dJlslXvoTg==",
+      "requires": {
+        "sprintf-js": "~1.0.2"
+      }
+    },
+    "balanced-match": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/balanced-match/-/balanced-match-1.0.0.tgz",
+      "integrity": "sha1-ibTRmasr7kneFk6gK4nORi1xt2c="
+    },
+    "brace-expansion": {
+      "version": "1.1.11",
+      "resolved": "https://registry.npmjs.org/brace-expansion/-/brace-expansion-1.1.11.tgz",
+      "integrity": "sha512-iCuPHDFgrHX7H2vEI/5xpz07zSHB00TpugqhmYtVmMO6518mCuRMoOYFldEBl0g187ufozdaHgWKcYFb61qGiA==",
+      "requires": {
+        "balanced-match": "^1.0.0",
+        "concat-map": "0.0.1"
+      }
+    },
+    "commander": {
+      "version": "2.9.0",
+      "resolved": "https://registry.npmjs.org/commander/-/commander-2.9.0.tgz",
+      "integrity": "sha1-nJkJQXbhIkDLItbFFGCYQA/g99Q=",
+      "requires": {
+        "graceful-readlink": ">= 1.0.0"
+      }
+    },
+    "concat-map": {
+      "version": "0.0.1",
+      "resolved": "https://registry.npmjs.org/concat-map/-/concat-map-0.0.1.tgz",
+      "integrity": "sha1-2Klr13/Wjfd5OnMDajug1UBdR3s="
+    },
+    "deep-extend": {
+      "version": "0.5.1",
+      "resolved": "https://registry.npmjs.org/deep-extend/-/deep-extend-0.5.1.tgz",
+      "integrity": "sha512-N8vBdOa+DF7zkRrDCsaOXoCs/E2fJfx9B9MrKnnSiHNh4ws7eSys6YQE4KvT1cecKmOASYQBhbKjeuDD9lT81w=="
+    },
+    "entities": {
+      "version": "2.0.3",
+      "resolved": "https://registry.npmjs.org/entities/-/entities-2.0.3.tgz",
+      "integrity": "sha512-MyoZ0jgnLvB2X3Lg5HqpFmn1kybDiIfEQmKzTb5apr51Rb+T3KdmMiqa70T+bhGnyv7bQ6WMj2QMHpGMmlrUYQ=="
+    },
+    "esprima": {
+      "version": "4.0.1",
+      "resolved": "https://registry.npmjs.org/esprima/-/esprima-4.0.1.tgz",
+      "integrity": "sha512-eGuFFw7Upda+g4p+QHvnW0RyTX/SVeJBDM/gCtMARO0cLuT2HcEKnTPvhjV6aGeqrCB/sbNop0Kszm0jsaWU4A=="
+    },
+    "fs.realpath": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/fs.realpath/-/fs.realpath-1.0.0.tgz",
+      "integrity": "sha1-FQStJSMVjKpA20onh8sBQRmU6k8="
+    },
+    "get-stdin": {
+      "version": "5.0.1",
+      "resolved": "https://registry.npmjs.org/get-stdin/-/get-stdin-5.0.1.tgz",
+      "integrity": "sha1-Ei4WFZHiH/TFJTAwVpPyDmOTo5g="
+    },
+    "glob": {
+      "version": "7.1.6",
+      "resolved": "https://registry.npmjs.org/glob/-/glob-7.1.6.tgz",
+      "integrity": "sha512-LwaxwyZ72Lk7vZINtNNrywX0ZuLyStrdDtabefZKAY5ZGJhVtgdznluResxNmPitE0SAO+O26sWTHeKSI2wMBA==",
+      "requires": {
+        "fs.realpath": "^1.0.0",
+        "inflight": "^1.0.4",
+        "inherits": "2",
+        "minimatch": "^3.0.4",
+        "once": "^1.3.0",
+        "path-is-absolute": "^1.0.0"
+      }
+    },
+    "graceful-readlink": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/graceful-readlink/-/graceful-readlink-1.0.1.tgz",
+      "integrity": "sha1-TK+tdrxi8C+gObL5Tpo906ORpyU="
+    },
+    "ignore": {
+      "version": "5.1.8",
+      "resolved": "https://registry.npmjs.org/ignore/-/ignore-5.1.8.tgz",
+      "integrity": "sha512-BMpfD7PpiETpBl/A6S498BaIJ6Y/ABT93ETbby2fP00v4EbvPBXWEoaR1UBPKs3iR53pJY7EtZk5KACI57i1Uw=="
+    },
+    "inflight": {
+      "version": "1.0.6",
+      "resolved": "https://registry.npmjs.org/inflight/-/inflight-1.0.6.tgz",
+      "integrity": "sha1-Sb1jMdfQLQwJvJEKEHW6gWW1bfk=",
+      "requires": {
+        "once": "^1.3.0",
+        "wrappy": "1"
+      }
+    },
+    "inherits": {
+      "version": "2.0.4",
+      "resolved": "https://registry.npmjs.org/inherits/-/inherits-2.0.4.tgz",
+      "integrity": "sha512-k/vGaX4/Yla3WzyMCvTQOXYeIHvqOKtnqBduzTHpzpQZzAskKMhZ2K+EnBiSM9zGSoIFeMpXKxa4dYeZIQqewQ=="
+    },
+    "ini": {
+      "version": "1.3.5",
+      "resolved": "https://registry.npmjs.org/ini/-/ini-1.3.5.tgz",
+      "integrity": "sha512-RZY5huIKCMRWDUqZlEi72f/lmXKMvuszcMBduliQ3nnWbx9X/ZBQO7DijMEYS9EhHBb2qacRUMtC7svLwe0lcw=="
+    },
+    "js-yaml": {
+      "version": "3.13.1",
+      "resolved": "https://registry.npmjs.org/js-yaml/-/js-yaml-3.13.1.tgz",
+      "integrity": "sha512-YfbcO7jXDdyj0DGxYVSlSeQNHbD7XPWvrVWeVUujrQEoZzWJIRrCPoyk6kL6IAjAG2IolMK4T0hNUe0HOUs5Jw==",
+      "requires": {
+        "argparse": "^1.0.7",
+        "esprima": "^4.0.0"
+      }
+    },
+    "jsonc-parser": {
+      "version": "2.2.1",
+      "resolved": "https://registry.npmjs.org/jsonc-parser/-/jsonc-parser-2.2.1.tgz",
+      "integrity": "sha512-o6/yDBYccGvTz1+QFevz6l6OBZ2+fMVu2JZ9CIhzsYRX4mjaK5IyX9eldUdCmga16zlgQxyrj5pt9kzuj2C02w=="
+    },
+    "linkify-it": {
+      "version": "2.2.0",
+      "resolved": "https://registry.npmjs.org/linkify-it/-/linkify-it-2.2.0.tgz",
+      "integrity": "sha512-GnAl/knGn+i1U/wjBz3akz2stz+HrHLsxMwHQGofCDfPvlf+gDKN58UtfmUquTY4/MXeE2x7k19KQmeoZi94Iw==",
+      "requires": {
+        "uc.micro": "^1.0.1"
+      }
+    },
+    "lodash.differencewith": {
+      "version": "4.5.0",
+      "resolved": "https://registry.npmjs.org/lodash.differencewith/-/lodash.differencewith-4.5.0.tgz",
+      "integrity": "sha1-uvr7yRi1UVTheRdqALsK76rIVLc="
+    },
+    "lodash.flatten": {
+      "version": "4.4.0",
+      "resolved": "https://registry.npmjs.org/lodash.flatten/-/lodash.flatten-4.4.0.tgz",
+      "integrity": "sha1-8xwiIlqWMtK7+OSt2+8kCqdlph8="
+    },
+    "markdown-it": {
+      "version": "10.0.0",
+      "resolved": "https://registry.npmjs.org/markdown-it/-/markdown-it-10.0.0.tgz",
+      "integrity": "sha512-YWOP1j7UbDNz+TumYP1kpwnP0aEa711cJjrAQrzd0UXlbJfc5aAq0F/PZHjiioqDC1NKgvIMX+o+9Bk7yuM2dg==",
+      "requires": {
+        "argparse": "^1.0.7",
+        "entities": "~2.0.0",
+        "linkify-it": "^2.0.0",
+        "mdurl": "^1.0.1",
+        "uc.micro": "^1.0.5"
+      }
+    },
+    "markdownlint": {
+      "version": "0.20.4",
+      "resolved": "https://registry.npmjs.org/markdownlint/-/markdownlint-0.20.4.tgz",
+      "integrity": "sha512-jpfaPgjT0OpeBbemjYNZbzGG3hCLcAIvrm/pEY3+q/szDScG6ZonDacqySVRJAv9glbo8y4wBPJ0wgW17+9GGA==",
+      "requires": {
+        "markdown-it": "10.0.0"
+      }
+    },
+    "markdownlint-cli": {
+      "version": "0.23.2",
+      "resolved": "https://registry.npmjs.org/markdownlint-cli/-/markdownlint-cli-0.23.2.tgz",
+      "integrity": "sha512-OSl5OZ8xzGN6z355cqRkiq67zPi3reJimklaF72p0554q85Dng5ToOjjSB9tDKZebSt85jX8cp+ruoQlPqOsPA==",
+      "requires": {
+        "commander": "~2.9.0",
+        "deep-extend": "~0.5.1",
+        "get-stdin": "~5.0.1",
+        "glob": "~7.1.2",
+        "ignore": "~5.1.4",
+        "js-yaml": "~3.13.1",
+        "jsonc-parser": "~2.2.0",
+        "lodash.differencewith": "~4.5.0",
+        "lodash.flatten": "~4.4.0",
+        "markdownlint": "~0.20.4",
+        "markdownlint-rule-helpers": "~0.11.0",
+        "minimatch": "~3.0.4",
+        "minimist": "~1.2.5",
+        "rc": "~1.2.7"
+      }
+    },
+    "markdownlint-rule-helpers": {
+      "version": "0.11.0",
+      "resolved": "https://registry.npmjs.org/markdownlint-rule-helpers/-/markdownlint-rule-helpers-0.11.0.tgz",
+      "integrity": "sha512-PhGii9dOiDJDXxiRMpK8N0FM9powprvRPsXALgkjlSPTwLh6ymH+iF3iUe3nq8KGu26tclFBlLL5xAGy/zb7FA=="
+    },
+    "mdurl": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/mdurl/-/mdurl-1.0.1.tgz",
+      "integrity": "sha1-/oWy7HWlkDfyrf7BAP1sYBdhFS4="
+    },
+    "minimatch": {
+      "version": "3.0.4",
+      "resolved": "https://registry.npmjs.org/minimatch/-/minimatch-3.0.4.tgz",
+      "integrity": "sha512-yJHVQEhyqPLUTgt9B83PXu6W3rx4MvvHvSUvToogpwoGDOUQ+yDrR0HRot+yOCdCO7u4hX3pWft6kWBBcqh0UA==",
+      "requires": {
+        "brace-expansion": "^1.1.7"
+      }
+    },
+    "minimist": {
+      "version": "1.2.5",
+      "resolved": "https://registry.npmjs.org/minimist/-/minimist-1.2.5.tgz",
+      "integrity": "sha512-FM9nNUYrRBAELZQT3xeZQ7fmMOBg6nWNmJKTcgsJeaLstP/UODVpGsr5OhXhhXg6f+qtJ8uiZ+PUxkDWcgIXLw=="
+    },
+    "once": {
+      "version": "1.4.0",
+      "resolved": "https://registry.npmjs.org/once/-/once-1.4.0.tgz",
+      "integrity": "sha1-WDsap3WWHUsROsF9nFC6753Xa9E=",
+      "requires": {
+        "wrappy": "1"
+      }
+    },
+    "path-is-absolute": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/path-is-absolute/-/path-is-absolute-1.0.1.tgz",
+      "integrity": "sha1-F0uSaHNVNP+8es5r9TpanhtcX18="
+    },
+    "rc": {
+      "version": "1.2.8",
+      "resolved": "https://registry.npmjs.org/rc/-/rc-1.2.8.tgz",
+      "integrity": "sha512-y3bGgqKj3QBdxLbLkomlohkvsA8gdAiUQlSBJnBhfn+BPxg4bc62d8TcBW15wavDfgexCgccckhcZvywyQYPOw==",
+      "requires": {
+        "deep-extend": "^0.6.0",
+        "ini": "~1.3.0",
+        "minimist": "^1.2.0",
+        "strip-json-comments": "~2.0.1"
+      },
+      "dependencies": {
+        "deep-extend": {
+          "version": "0.6.0",
+          "resolved": "https://registry.npmjs.org/deep-extend/-/deep-extend-0.6.0.tgz",
+          "integrity": "sha512-LOHxIOaPYdHlJRtCQfDIVZtfw/ufM8+rVj649RIHzcm/vGwQRXFt6OPqIFWsm2XEMrNIEtWR64sY1LEKD2vAOA=="
+        }
+      }
+    },
+    "sprintf-js": {
+      "version": "1.0.3",
+      "resolved": "https://registry.npmjs.org/sprintf-js/-/sprintf-js-1.0.3.tgz",
+      "integrity": "sha1-BOaSb2YolTVPPdAVIDYzuFcpfiw="
+    },
+    "strip-json-comments": {
+      "version": "2.0.1",
+      "resolved": "https://registry.npmjs.org/strip-json-comments/-/strip-json-comments-2.0.1.tgz",
+      "integrity": "sha1-PFMZQukIwml8DsNEhYwobHygpgo="
+    },
+    "uc.micro": {
+      "version": "1.0.6",
+      "resolved": "https://registry.npmjs.org/uc.micro/-/uc.micro-1.0.6.tgz",
+      "integrity": "sha512-8Y75pvTYkLJW2hWQHXxoqRgV7qb9B+9vFEtidML+7koHUFapnVJAZ6cKs+Qjz5Aw3aZWHMC6u0wJE3At+nSGwA=="
+    },
+    "wrappy": {
+      "version": "1.0.2",
+      "resolved": "https://registry.npmjs.org/wrappy/-/wrappy-1.0.2.tgz",
+      "integrity": "sha1-tSQ9jz7BqjXxNkYFvA0QNuMKtp8="
+    }
+  }
+}
diff --git a/tools/precommit/package.json b/tools/precommit/package.json
new file mode 100644
index 0000000000..08ed3db6d2
--- /dev/null
+++ b/tools/precommit/package.json
@@ -0,0 +1,20 @@
+{
+  "name": "cp2k-precommit",
+  "version": "1.0.0",
+  "description": "Tools used by the cp2k-precomit system",
+  "main": "index.js",
+  "repository": "",
+  "scripts": {
+    "test": "echo \"Error: no test specified\" && exit 1"
+  },
+  "repository": {
+      "type": "git",
+      "url": ""
+   },
+  "keywords": [],
+  "author": "",
+  "license": "ISC",
+  "dependencies": {
+    "markdownlint-cli": "^0.23.2"
+  }
+}
diff --git a/tools/precommit/requirements.txt b/tools/precommit/requirements.txt
new file mode 100644
index 0000000000..73720e2176
--- /dev/null
+++ b/tools/precommit/requirements.txt
@@ -0,0 +1,14 @@
+appdirs==1.4.4
+attrs==20.1.0
+black==19.10b0
+click==7.1.2
+Flask==1.1.2
+gunicorn==20.0.4
+itsdangerous==1.1.0
+Jinja2==2.11.2
+MarkupSafe==1.1.1
+pathspec==0.8.0
+regex==2020.7.14
+toml==0.10.1
+typed-ast==1.4.1
+Werkzeug==1.0.1